CVE-2018-1061

MEDIUMNVD 6.57.5▲

6.5

python before versions 2.7.15, 3.4.9, 3.5.6rc1, 3.6.5rc1 and 3.7.0 is vulnerable to catastrophic backtracking in the difflib.IS_LINE_JUNK method. An attacker could use this flaw to cause denial of service.

CVSS v3: 6.5
EG Score: 7.5(medium)
EPSS: 83.1%
KEV: Not listed

Published

June 19, 2018

Last Modified

November 21, 2024

References (42)

secalert@redhathttp://lists.opensuse.org/opensuse-security-announce/2020-01/msg00040.html
secalert@redhathttp://www.securitytracker.com/id/1042001
secalert@redhathttps://access.redhat.com/errata/RHBA-2019:0327
secalert@redhathttps://access.redhat.com/errata/RHSA-2018:3041
secalert@redhathttps://access.redhat.com/errata/RHSA-2018:3505
secalert@redhathttps://access.redhat.com/errata/RHSA-2019:1260
secalert@redhathttps://access.redhat.com/errata/RHSA-2019:3725
secalert@redhathttps://bugs.python.org/issue32981
secalert@redhathttps://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-1061
secalert@redhathttps://docs.python.org/3.5/whatsnew/changelog.html#python-3-5-6-release-candidate-1
secalert@redhathttps://docs.python.org/3.6/whatsnew/changelog.html#python-3-6-5-release-candidate-1
secalert@redhathttps://lists.debian.org/debian-lts-announce/2018/09/msg00030.html
secalert@redhathttps://lists.debian.org/debian-lts-announce/2018/09/msg00031.html
secalert@redhathttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/46PVWY5LFP4BRPG3BVQ5QEEFYBVEXHCK/
secalert@redhathttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AEZ5IQT7OF7Q2NCGIVABOWYGKO7YU3NJ/

Patch Availability(8)

Vendor / Ecosystem	Fixed in / Patch	Released	Source
ubuntu	python2.7 (2.7.3-0ubuntu3.11) @ precise	2026-05-28	ubuntu
ubuntu	python3.5-venv (3.5.2-2ubuntu0~16.04.5) @ xenial	2026-05-28	ubuntu
ubuntu	python3.8-venv (3.8.0-3ubuntu1~18.04.2+esm2) @ bionic	2026-05-28	ubuntu
redhat	python-0:2.7.5-63.el7_4	2020-04-07	redhat
redhat	python-0:2.7.5-74.el7_5	2020-04-01	redhat
redhat	rh-python36-python-0:3.6.9-2.el7	2019-11-06	redhat
redhat	python27-python-jinja2-0:2.6-15.el7	2019-05-22	redhat
redhat	python-0:2.7.5-76.el7	2018-10-30	redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

CWE-20Improper Input Validation

All Vendor Advisories

(8)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 11× in last 7d / 20× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

2026-06-08 14:14 UTCEPSS rescore
2026-06-08 14:14 UTCEPSS rescore
2026-06-07 15:22 UTCEPSS rescore
2026-06-07 15:22 UTCEPSS rescore
2026-06-05 22:45 UTCEPSS rescore
2026-06-05 22:45 UTCEPSS rescore
2026-06-05 06:08 UTCEPSS rescore
2026-06-05 06:08 UTCEPSS rescore
2026-06-04 13:10 UTCEPSS rescore
2026-06-02 20:11 UTCEPSS rescore
2026-06-02 20:11 UTCEPSS rescore
2026-06-01 13:50 UTCEPSS rescore
2026-06-01 13:50 UTCEPSS rescore
2026-05-31 22:29 UTCEPSS rescore
2026-05-31 00:14 UTCEPSS rescore
2026-05-31 00:14 UTCEPSS rescore
2026-05-29 13:41 UTCEPSS rescore
2026-05-28 13:42 UTCEPSS rescore
2026-05-28 13:42 UTCEPSS rescore
2026-05-28 06:31 UTCEG score recompute

Frequently asked(5)

What is CVE-2018-1061?

CVE-2018-1061 is a medium vulnerability published on June 19, 2018. python before versions 2.7.15, 3.4.9, 3.5.6rc1, 3.6.5rc1 and 3.7.0 is vulnerable to catastrophic backtracking in the difflib.ISLINEJUNK method. An attacker could use this flaw to cause denial of service.

When was CVE-2018-1061 disclosed?

CVE-2018-1061 was first published in the National Vulnerability Database on June 19, 2018, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.

Is CVE-2018-1061 actively exploited?

CVE-2018-1061 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 83.1% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.

What is the CVSS score of CVE-2018-1061?

CVE-2018-1061 has a CVSS v3 base score of 6.5 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 7.5.

How do I remediate CVE-2018-1061?

Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2018-1061, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2018-1061

Explore →

Is Your Infrastructure Affected by CVE-2018-1061?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs

CVE-2018-1061

Published

Last Modified

References (42)

Patch Availability(8)

Weakness Classification(1)

All Vendor Advisories

Data Freshness Timeline

Frequently asked(5)

Dependency Blast Radius

Is Your Infrastructure Affected by CVE-2018-1061?

Same vendor

Same CWE

CVE-2018-1061

📅 Published

🔄 Last Modified

🔗 References (42)

Patch Availability(8)

Weakness Classification(1)

All Vendor Advisories

Data Freshness Timeline

❓ Frequently asked(5)

Dependency Blast Radius

Is Your Infrastructure Affected by CVE-2018-1061?

🔗 Related CVEs(same vendor + same CWE)

Same vendor

Same CWE

Published

Last Modified

References (42)

Frequently asked(5)

Related CVEs(same vendor + same CWE)